Oldham coupling is also known as metal cross slider coupling. Its Oldham coupling is in a circular shape and is made of steel or wear-resistant alloy. Cross slider coupling is suitable for transmission with low speed and large torque. Oldham coupling consists of two sleeves and a center slider. As a component for transmitting torque, the center slider is usually made of engineering plastics. In special cases, other materials such as metal materials can be selected.
Structure
The material of the coupling parts can be 45 steel, which increases the dynamic load and wear. Therefore, when selecting, it should be noted that its working speed should not be greater than the specified value. This coupling is generally used for speed n<250r/min, the shaft has a large stiffness, and there is no severe impact.
● The structure of the Oldham coupling is similar to that of the cross Oldham coupling. The difference is that the middle cross slider is a square slider, and the middle slider is used to slide in the corresponding radial grooves on the end faces of the half couplings on both sides to achieve the connection of the two half couplings. This coupling has high noise, low efficiency, and fast wear. It is generally not used as much as possible. Only in very low speed occasions, the slider coupling specified in this standard is suitable for oil pump devices or other occasions with small torque transmission. It has a certain compensation for the relative offset of the two shafts, shock absorption and buffering performance; its working temperature is -20~70°C. The nominal torque transmitted is 16~500N.m.
● Allowable compensation amount: axial △ x=1~2mm, radial △ y ≤ 0.2mm, angular △α≤ 40 ′.
Features
The material of the slider coupling parts can be 45 steel, and the working surface needs to be heat treated to improve its hardness; Q275 steel can also be used when the requirements are lower, without heat treatment. In order to reduce friction and wear, oil should be injected from the oil hole of the intermediate disk for lubrication during use. Because the half coupling and the intermediate disk form a moving pair and cannot rotate relative to each other, the angular velocity of the driving shaft and the driven shaft should be equal. However, when working with relative displacement between the two shafts, the intermediate disk will generate a large centrifugal force, thereby increasing the dynamic load and wear. Therefore, when selecting, it should be noted that its operating speed should not exceed the specified value. This coupling is generally used for speeds n<250r/min, the rigidity of the shaft is large, and there is no severe impact.
The center slider and the sleeve are matched with a small pressure, which can make the coupling run with zero clearance during equipment operation. As the use time increases, the slider may lose the function of no recoil due to wear, but the center slider is not expensive and is easy to replace. After replacement, it can still play its original performance. Slider couplings are commonly used in general motors. In some cases, they can also be used to connect servo motors. During use, the relative displacement is corrected by sliding the center slider. Because the friction between the slider and the sleeve resists the relative displacement, the bearing load between them will not increase due to the increase in relative displacement.
Advantages
The slider coupling can eliminate the additional load between the shafts during the automatic control of the motor. The fixed body uses splines for sliding, and the inner and outer sleeves inside the sliding body can slide relative to each other in the axial direction. The coupling can realize the integration of sliding and rotation. Under the condition of equal rotation and diameter, the shortest dimension is much smaller than the cross shaft. It improves the uniformity of load distribution on the working surface and can transmit larger torque, but the elasticity is slightly reduced.
Applications
Unlike other couplings, the slider coupling does not have an elastic element that works like a spring, so the bearing load will not increase due to the increase in the relative displacement between the shafts. In any case, this series of couplings is more value for money, and the ability to choose sliders of different materials is the biggest advantage of this coupling. The company can provide a variety of raw material center sliders to suit different applications according to the specific requirements of customers. Generally speaking, one type of material is suitable for zero clearance, high torque rigidity and high torque, and the other type of material is suitable for low-precision positioning, no zero clearance, but with vibration absorption and noise reduction functions. Non-metallic sliders also have excellent electrical insulation and can act as mechanical fuses. When the engineering plastic slider is damaged, the transmission function will be completely terminated, thereby protecting valuable mechanical parts. This design is suitable for large parallel relative displacements. The three-part design of the slider coupling limits its ability to compensate for axial deviations, such as it cannot be used in push-pull applications. At the same time, because the center slider is floating, the movement of the two axes must ensure that the slider will not fall off.
LK25 Stainless Steel & Copper Oldham Coupling (Setscrew Type).pdf
LK25 Stainless Steel & Copper Oldham Coupling (Clamping Type).pdf
